Synthetic resins, photographic process, and media



Patented June 1 1926 UNITED STATES PATENT OFFICE.

MURRAY C. BEEBE, ALEXANDER MURRAY, AND HAROLD V. HERLINGER, OF CINCIN- NATI, OHIO, ASSIGNORS TO THE WADSWORTH WATCH CASE COMPANY, OF DAYTON,

KENTUCKY, A CORPORATION.

SYNTHETIC RESINS, PHOTOGRAPHIC PROCESS, AND MEDIA.

Io Drawing.

Our invention relates particularly to an improved photographic process, wherein synthetic resins are employed as media for producing an image, design, or character,

5 and the inventionv relates further to improved media for photographic purposes.

In the practice of the invention, we utilize a class of chemical compounds for photographic purposes which hitherto has not been considered available for such purposes; a class which affords a simple medium which can be readily applied as a coating to metallic surfaces, or other surfaces, or which may be employed in any other suitable manner;

a class of materials which is sensitive to the action of light to a greater or less degree, without the addition of accelerators, or sensitizers, but with which suitable sensitizers may be incorporated; a class of materials which produces a print which is readil developable with simple solvents; which a fords a medium which forms an unusually good resist against the action of etching agents when the developed print is on a surface that is to be subsequently etched, for

printing or other purposes; and which affords a medium depending upon its production on inexpensive materials, such as furfural, acetone, etc., whose source of supply is practically unlimited.

The principal ingredients which we use have not been classed hitherto with photographic materials. The class of compounds which has been found by us to possess remarkable adaptability to the preparation of light-sensitive media includes that group of materials containing five memberedmonohe'terocyclic compounds, comprising the furfuranepyrrol-th1ophene group, derived from the following parent compounds. Typical examples of these compounds are here given:

0 -on 'Ihlophene.

o -cn Furlumne.

Application filed November 18, 1922. Serial No. 601,827.

methods, or by any approved method. For example, a resin may be produced by condensing furfural through the use of variousreagents, such as aniline, hydrochloric acid, ammonia, acetone, methyl ethyl ketone, alpha-naphthylamine, sodium hydroxide, etc. While the production of resins of this general character is known and described in the literature, it has not been known hitherto that such synthetic resins can be employed advantageously in the photographic arts. The resins,or resin-like materials, produced from the compounds referred to above appear to be condensations, or polymerizations.

Our invention, in one aspect, lies in the application of one or more of these fivemembered ring, heterocyclic compounds referred to above, or derivatives of the same, to photographic. purposes; When, for example, such materials are applied as a film to a metallic surface, a lass surface,'or other desired surface, as by owing, spreading, or I otherwise, preferably in the form of a solution of the resin having a consistency of a lacquer, or thin solution, they are so sensitive to 1i ht as to enable them to be readily utilized for photographic purposes. Photographic images may be formed readily in such media, and may be developed through the use of suitable solvents, selective dyeing, or the like.

The exact chemical reactions which bring about these radically new results are not fully known, but may, by reasonable hypothesis, be attributed to what we may designate as photo-condensation, photooxidation, photoresmification, or photo-polymerization. As heretofore stated, a furfural resin coating is in itself light sensitive to a remarkable degree without the addition of accelerators or sensitizers; yet, under certain conditions, the inclusion of sensitizers does produce acceleration.

There are many practical applications of our process, such as decorating metallic or other surfaces through the inclusion of a de sired color with the coating, preparation of lithographic plates, half-tone process plates, intaglio printing plates, etc. Screenless photo litho-plates may be produced from continuous-tone negatives because the coating becomes variably permeable to etching reagents in an inverse ratio to the light intensity of the luminous rays to which the coating has been exposed.

We have found that pyrrol and thiophene condensation products similarly produced have shown light sensitivity. These, as already stated, are alternative compounds in our process.

As examples in the practical applications of our process, we may instance the follow- (a) Furfuramide resin:

A mixture of 100 grams of furfural and 100 grams of concentrated ammonium hydroxide is introduced into a flask at room temperature. Condensation may be effected under gentle heating, if necessary. The resinous product is dried, after being separated from the-entrained water, by heating to 105 degrees C. for an hour, and, when dissolved in benzene or acetone, is applied as a thin film onto the surface upon which the photographic print is to be made. Printing may be done by contact or by optical projection as desired, the time varying frogn one to five minutes, depending on the den ity of the negative, etc. After printing the image may be developed in a 25% solution of benzol (benzene) in turpentine which gives good results. The sensitivity can be increased by adding a halo en source, such as small percentages of i0 oform, methyl iodide, iodine, or ammonium bichromate, so that contact prints are produced under an are light in two and one-half minutes, instead of five,

without the inclusion of a sensitizer.

Among the most sensitive substances which we have found are the furfural-ketone resins of which the following is a practical exam 1e:

b) Furfuracetone resin:

A condensation product is produced by applying heat at about 100 degrees C. to 90 ams of furfural in 58 grams of acetone combined with 100 grams of concentrated solution of sodium hydroxide, as a condens ing agent, in a reflux condenser for half an hour. The resulting product is somewhat viscous, and may be directly diluted by a suitable thinner, such as benzol, or acetone, to form a sensitive film of any desired consistency; Acetone is here given as an example of a ketone.

The condensation product may be purified and recovered by neutralizing the sodium hydroxide with acid, or acid solution, decanting, and drying the precipitate at 105 degrees C. Prints are made in the remarkably short time of ten seconds by contact printing under an are light. Sensitizers, such as iodoform, colloidal iodide, etc., may be added if desired.

As an exemplification of photo condensation, in which furfural is used, we have found the following of practical value:

(0) Direct photo condensation:

60 grams of furfural and 40 grams of aniline are mixed, and the mixture applied directly asathin film-to a suitable surface;

or, the materials are incorporated in a suit able medium, such as cellulose acetate, asphaltum, cumar resin, etc., which may in themselves be sensitive to light. When exposed to an are light, such a mixture becomes resinous in about five minutes. In contrast to this, furfural and aniline condense only slowly without the aid of light, even when boiled together.

As another modification, the following is given:

(0?) Indirect photo condensation.

The addition of small quantities of iodine in amixture of furfural and aniline in the dark produces a viscous condensation product of a deep red color. To produce prints rapidly by means of this reaction, a mixture of furfural and aniline is sensitized by adding a small amount of iodoform, or any compound which will liberate iodine when it is exposed to light. With such a medium, accelerated reaction progresses directly upon the support which is to receive the image. A deep red coloration results under a 30 seconds exposure wherever the light has been permitted to act; and, with continuous tone negatives, the depth of color is proportional to the intensity of the light, producing a highly visible image. If desired as an etching resist on a metallic or other surface, this mediumnsed alone or combined with another, such as cellulose acetate, may be de- Pyw'ol product.

(6) Resinous pyrrol condensation products.

We have distilled pyrrol to purify it, and have found that the sticky resinous residue is sensitive to light, producing a print in eight minutes. After sensitization with iodoform, a print was roduced in six minutes. As an alternative to this, ten grams of purified pyrrol were added to seven grams of concentrated sulphuric acid, when another resinous substance was produced. After being dried, dissolved in benzene, and applied as a film, it was found to be so light sensitive as to produce a print in two minutes.

The foregoing examples are given merely as illustrative of the invention or discovery. The invention is adaptable to a wide variety of industrial uses. Coatings, or films, produced from these media are especially resistant to the action of acids, as for etching in relief or intaglio, but more permanent in this respect than asphaltum; and the sensi- *tivity of the media is also greater than that of asphaltum.

Whileit is preferred to employ solutions of the synthetic'resins and apply such solutions as thin coatings to suitable surfaces,. the mventi-on is not to be understood as heterocyclic compounds is used herein to indicate those compounds in whlch one member of the ring is an element other than carbon, as for example, oxygen, nitrogen, sul- "phur, etc. The expression developing the image 'as used herein is intended to be broad enough to include any suitable method of treating the film, or image, subsequent to the formation of the latent image, to renderthe image useful for whatever purpose it is to be employed. This. includes desensitizing unacted upon portions of the film,

removal ;of unacted upon portions of the I film, or vice versa, the use of mordants, dyes,

- The'foregoing detailed description has been given for clearness of understanding only, and no unnecessary limitations should beunderstood therefrom, but the appended claims should be construed as broadly as permissible, in view of the prior art.

What we regard as new, and desire to secure by Letters Patent, is:

1. The process which comprises photographically forming an image, design or character which embodies a resinous product of a five-membered mono-heterocychc compound.

2. The process which comprises applying to a metal surface a film comprising a solution of a resinous product of a five-membered mono-heterocyclic compound and photographicall forming a resistant" image embodying sai resinous product.

3. The process of roducing an image, design or character which comprises acting selectively with light upon a body comprising a resinous product of a jfive-membered mono-heterocyclic compound in accordance with an image, design or character, to effect the desired transformation.

4. The process of producing an image, design or character which comprises acting selectively with light upon a body comprising a resinous product of a five-membered mono-heterocychc compound in accordance with an image, design or character, to effect the desired transformation, and developing the image.

5. The rocess which comprises applying to a suita 1e surface a coating comprising a solution of a resinous product of a fivemembered mono-heterocyclic compound and acting selectively with light upon said coatderived from furfurals.

ing in accordance with an image, design or character, to efiect the desired transformation.

6. The grocesswhich comprises applyingto a suita 1e surface a coating comprising a solution of a resinous product. of a live membered mono-heterocyclic compound and acting selectively with light upon said coating in accordance with an image, design or.

character, to effect the desired transformation, and developing the image.

7. The process 'Wl'llCh comprises photographically forming an image, design or character whloh embodies a resinous product 8. The process-of producing an image, design or character which comprises acting selectively with light upon a body comprising a resinous product derived from furfurals in accordance with an image, design or character, to effect the desired transformation.

9. The process of producing an image, design or character which comprises acting selectively with light upon a bodycomprismg a resinous 'roduct derived from furfurals, in accor ance with an image, design or character, to effect the desired transformation, and developing the image.

' 10. The process which comprises applying to a desired surface a solution of a resin derived from the furfurals, acting selectively with light upon the film thus produced upon an image, design or character by acting selectively with light upon a body comprising a condensation product of a furfural and a ketone in accordance with an image, de-

sign or character, to-efi'ect the desired transformation, anddeveloping the image.

14. The process which comprises applying to a suitable surface a solution of a condensation product of a furfural and a ketone to form a film on said surface, and acting selectively with light upon said iilm in accordance with an image, design or character, to effect the desired transformation. 1

' 15.;The process which comprises applying to a suitable surface a solution of a condensation product of a furfural and a ketone to form a film on said surface, acting selecfural and ethyl methyl ketone, acting selec character which embodies a condensation product of a furfural and ethyl methyl ketone.

17. The process of producing an image, design or character which comprises acting selectively with light upon a body comprising a condensation product of a furfural and ethyl methyl ketone in accordance with an image, design or character to effect the desiredtransformation. 1 v

18. The process of producing an image, design or character which comprises acting selectively with light upon a body comprising a condensation product of a furfural and, ethyl methyl ketone in accordance with an image, design or character to effect the desired transformation, and developing the image.

19. The process which comprises applying to a suitable surface a film comprising a solution of a condensation product of a furtively with light upon said fihn in accordance with an image, design or characterto effect the desired transformation, and developing the image- 20. The process which comprises photographically forming an image, design or character which embodies a resinous product of a five-membered mono-heterocycliccompound having incorporated therewith a SBIlSltlZBI. 21. The process of producing an image,

design or character which comprises acting selectively with light upon a body comprising a resinous product of a five-membered mono-heterocyclic compound and a sen'sitizer incorporated therewith, in accordance with an image, design or character, to effect the desired transformation.

22. The process which comprises applying to a suitable surface a film comprising a solution of 'a resinous product of a five-mem-- bered mono-heterocyclic substance having incorporated therewith a sensitizer, and acting selectively with light upon said film in accordance with an image, design or character, to effect the desired transformation.

23. The process which comprises photographically forming an .image, design or character which embodies a condensation 1 product of a furfural and a, ketone, having incorporated therewith a sensitizer.

24. The process of producing an image, design or c aracter which comprises acting selectively with light upon a body com ris-' ing a condensation product of a fur ral and a ketone associatedwith a small percentage of a sensitizer, in accordance with an image, design or'character, toeffect the desired transformation.

25. The processwhich'comprises applying to a suitable surface a fihn comprisinigua solution of a condensation product of a rfural and a ketone associated with a small percentage ofa sensitizer, acting selectively with light upon said film in accordance with an image, design or character, to efi'ect the desired transformation, and developing the lmage.

26. The process of producing an image, design or character which comprises acting selectively with light upon a body comprising a resinous product of a five-membered mono-heterocyclic compound, associated with a sensitizer comprising a halogen source, in

accordance with an image, design or character, to eli'ect the desired transformation.

27. The process of producing an image, design or character which comprises acting selectively with light upon a body comprisin" a condensation roduct of a furfural and a lietone, associates with a sensitizer comprising a halogen source, in accordance with an image, design or character, to eflect the desired transformation.

28. A photographic medium .com rising a resinous material derived from a. ve-membered mono-heterocyclic compound, associated with a sensitizer. I I

29. A photographic medium com rising a resinousmaterial derivedjrom a ve-membered mono-heterocyclic compound, associated with a sensitizer comprising a halogen 'ketone, associated with a sensitizer.

32. A photogra hic'medium comprisin a condensation pro not of a furfural an a ketone, associated with a sensitizer comprising a halogen source.

33. A photographic medium comprisin a condensation product of a furfura-l an a ketone, associated. with a sensitizer, and a solvent in which said materials are dispersed.

34. A photographic print comprising an image formed in accordance with the selective action of light in a body com rising a resinous material derived from a ve-membered mono-heterocyclic compound.

35. A protographic rint comprising an image formed In accor ance with the selective action of light in a. body comprising a condensation product of a furfural.

36. A photographic (printcomprising an image formed 1n accor ance with the selective action of light in a body comprising'a condensation product ofa furfural and a ketone. v Q,

37. A photographic rint comprising an image formed 1n accor ancewith the selec-v tive action of light in a body comprising a{ condensation product of'a furfural and an. ethyl-methyl'ketonei I Y 38! Means for receiving photographic impressions, comprising a suitable foundation and a film thereon comprising a resinous product derived from a monoheteratomic five-membered ring compound. c

39. A. photographic plate comprising a. suitable foundation, and a film thereon comprising a condensation'product of furfural.

40. A photographic. plate comprising a' prising a condensation suitable foundation, and a film thereon comproduct ofa furfural and a ketone. v y

41. A photographic plate comprising a suitable foundatiom and .a film thereon com-' prising. a condensation product of a furfural and. ethyl methyl ketone' 42 A photographic plate comprising a 25 -suitable foundation, and a film thereon, comprising a condensation product of a furfural and a sensitizer assoclated dens-atlon product.

tures. v

MURRAY-CL BEEBE. v A ALEXANDER'MURRAY. {HAROLD V. HERLINGER.

with said con- In testimony -ivvhereof we afiix our sig na 

